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Maximum power transfer theorem

  1. Mar 14, 2010 #1
    i was solving one question...it said find out value of r in a circuit so that the 6 ohm resistor consumes maximum power.....i applied max power theorem .....and calculated the thevenin eqivalent resistance accrss 6 ohm resistance....and put it equal to 6.....but the r cam eout to be negative...so wat to conclude from this...
  2. jcsd
  3. Mar 14, 2010 #2


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    Science Advisor

    It would help if you posted a diagram of the circuit in question. If this is an ideal source in series with a source resistance and the 6 ohm resistor, then this question is best answered by thinking about the following question:

    What is the max power transfer theorem?

    I suspect a Mod will be by shortly to move this question, but homework questions like these should be posed in the Homework section:
  4. Mar 14, 2010 #3
    yes...its just an ideal source...some resistances and a 6 ohm resistance...i just removed it and found out thevenin equivalent across its terminals...and compared it to be 6 for max theorem..i am attaching a file

    Attached Files:

  5. Mar 16, 2010 #4


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    As you surmise, max power transfer happens when the load resistance is equal to the source resistance. Have you determined the Thevenin equivalent of the circuit connected to the 6 ohm resistor (i.e. everything to the left of that resistor)?
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